Recreational overuse of alcohol among adolescent populations remains a significant and growing public health concern. Surveys report that 10% of eighth graders and up to a third of high school seniors consume binge quantities of alcohol on at least a biweekly basis. Heavy drinking during this critical period of formal education and significant brain development may pose serious risk for later intellectual and cognitive function. The proposed studies will develop a novel nonhuman primate model to evaluate the consequences of heavy drinking during adolescence task acquisition and performance in a range of cognitive domains. The Aims under investigation are 1) To determine if chronic oral alcohol intake slows acquisition of a battery of cognitive and behavioral tests in peri-adolescent monkeys; 2) To determine the cognitive and behavioral effects of withdrawal from chronic alcohol exposure; and 3) To determine if a history of chronic oral alcohol intake alters monkeys' cognitive and behavioral sensitivity to challenge with specific psychoactive compounds. Peri-adolescent monkeys will be trained on a battery of tests which probe learning, memory, attention and motor functions. A flavorant-fade procedure will be used to generate consistent, high levels of alcohol drinking in the experimental group which will be allowed to orally self-administer alcohol (M-F) throughout the 18 month test acquisition period. Radiotelemetric measurement of circadian patterns of body temperature and locomotor activity, and cerebrospinal fluid monoamine / metabolite concentrations will be used as correlates for the behavioral measures. Access to alcohol will be discontinued following acquisition of all behavioral tests to evaluate possible effects of withdrawal on the behavioral and physiological measures. Acute doses of psychoactive compounds will be employed to probe possible persisting behavioral sensitivities to serotonergic, dopaminergic, GABAergic or glutamatergic challenge. This exploratory study will provide evidence regarding the risks posed to cognition by heavy alcohol drinking in the peri-adolescent period.